The present invention relates to a new and improved fastener which is held against axial and rotational movement relative to a base member by an interaction between the base member and the fastener.
A known fastener which is received in a base member and held against axial and rotational movement relative to the base member is disclosed in U.S. Pat. No. 3,399,705. This known fastener includes a head section and an axially extending shank section. An indenting flange is formed on the head section to cause metal of a base member to be forced radially inwardly to grip a polygonal shank of the fastener. This holds the fastener against rotational movement relative to the base member. The fastener is held against axial movement relative to the base member by a bulge formed on the shank section of the fastener.
This known fastener is generally satisfactory in its mode of operation. However, it is desirable to enhance the rotation resisting or torque out characteristics of the known fastener. In addition, it is desirable to increase the ability of the known fastener to resist axial movement.